Drain the sour cherries well, preferably squeezing them out a little. Mix the espresso and amaretto together. Mix the mascarpone, low-fat quark, vanilla powder, sugar, carob flour and 1/4 of the amaretto-espresso mixture well to a creamy mass.
Place a layer of ladyfingers in a flat, preferably rectangular glass or porcelain dish. Sprinkle evenly with half of the remaining amaretto espresso mixture. Pour a third of the cream on top and cover with all the cherries close together. Spread the second third of the cream on top and cover with the remaining ladyfingers. Drizzle evenly over the rest of the amaretto espresso mixture. Spread the rest of the cream loosely on top of it.
Cover and put in the refrigerator for 2-3 hours. Dust evenly with cocoa powder before serving. Garnish with amarettini and amaretto cherries and possibly with mint or lemon balm leaves.